Baked dishes incorporating pastry crusts or shells underlying, and some cases, completely surrounding, fillings of various types, are very popular and have been known since ancient times. Pastry crusts typically comprise a powdered flour, e.g., wheat or graham flour, mixed with eggs and an animal or vegetable fat, e.g., lard, butter, or margarine, to form a viscous ball that is rolled out into a flat sheet, wrapped around a filling of some type, and then baked, both to cook the dough and filling, and to impart a measure of structural rigidity to the resulting confection. Because even a baked crust or shell lacks any inherent strength or rigidity, many pastry dishes, such as pies, tarts, tartlets, and quiches are prepared for baking in open topped baking pans or dishes, into which the rolled sheet of pastry dough is first laid and then conformingly pressed by hand, with any excess material, or “scrap,” being trimmed away at the upper margin of the pan with a knife, again, typically by hand.
In light of the foregoing, relatively labor-intensive processes involved in the production of pastry shells, some efforts have been made by restaurant and commercial bakery equipment makers to develop semi-automated methods and apparatus for producing pastry shells at a relatively greater speed and in a higher volume. Examples of these may be found in the patent literature in, e.g., U.S. Pat. Nos. 3,669,605 and 4,973,240 to A. J. Reilly, and involve a hydraulic press mounting one or more pairs of frustoconical dies and operative to conformingly press pre-measured volumes of pastry dough into conventional circular pie pans having a rim, closed bottoms and continuous, tapering, or upwardly flaring, side walls.
While such prior art efforts have met with some success, they are not without certain limitations. Among these is that they employ the conventional baking pans described above as female dies. Such pans are typically stamped or drawn from a flat sheet of a ductile metal to incorporate a closed bottom, or floor. Since such processes are incapable of producing relatively sharp bends and corners, i. e., 90° or less, they result in baking pans, and hence, pastry shells, with broadly tapered sidewalls that are either circular, or which intersect each other and the floor of the pan or crust at relatively large radii. However, for both cosmetic and product presentation reasons, and for reasons of storage and shipping efficiency, it is desirable to make rimless, open-topped pastry shells having a floor and continuous, substantially vertical side walls that can intersect each other and the floor of the pan at relatively sharp corners, in a wide variety of more complex ornamental plan form shapes, such as squares, crosses, triangles and the like, thus necessitating baking pans having a corresponding floor and corresponding continuous vertical curvilinear and/or polygonal sidewalls that intersect each other and the floor of the pan at relatively sharp corners.